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Africa Vetus

...to include Arae Philaenorum, at the southernmost point of the Gulf of Sidra. In the west he combined the old province of Africa Vetus (“Old Africa”) with what Caesar had designated as
Africa Nova (“New Africa”)—the old kingdoms of Numidia and Mauretania—so that the province’s western boundary was the Ampsaga (modern Rhumel) River in modern northeastern...

formation

...I (
c. 60–46
bc), who supported the Pompeian side in the Roman civil war between Pompey the Great and Julius Caesar. The kingdom fell in 46
bc at the Battle of Thapsus. A new province,
Africa Nova, was formed from the most developed part of the old Numidian kingdom east of the Ampsaga; it was subsequently (before 27
bc) amalgamated with the original province of Africa by...